During the past year proteins from chikungunya were used to test genetic vaccines constructs. Efforts were focused on testing the ability of DNA and/or virus like particle vaccines (VLPs)expressing different strains of CHIKV viral proteins determine their ability to induce potent immune responses in small animal models and non human primate models. Specifically, neutralizing antibodies and T cell responses were measured and the different types of vectors were compared. VLPs induced high levels of neutralizing antibodies and induced a higher response than DNA vectors. Studies were also initiated to determine whether VLPs could be constructed to induce similar types of immune reponses against other viruses of the genus Alphavirus, Family Togaviridae, including Western Equine Encephalitis virus (WEEV), Eastern Equine Encephalitis virus (EEEV), and Venezuelan Equine Encephalitis virus (VEEV). Specific modifications were introduced into vectors expressing the VLPs, resulting in much higher yields of several different alphaviruses than had been previously achieved. In addition, a collaboration with investigators at Washington University and Purdue was initiated to test neutralizing antibodies and to study the structure of the chikungunya virus to provide information for development of more effective vaccines. A CRADA was initiated with Merck to develop second generation Chikungunya VLP vaccines.